The race is a dead heat, the poll found. The gap between the two candidates, one a sitting congresswoman from Hawaii’s 2nd Congressional District, the other a former representative of that district, is within the poll’s margin of error of +/- 2.7 percent.

The automated telephone survey of 1,358 likely voters found Case at 41 percent, Hirono at 39 percent, with 8 percent saying neither candidate and 12 percent still unsure. The poll was conducted on January 18 and 19.

The winner of the Aug. 11 Democratic primary election is expected to face former Gov. Linda Lingle in a race that’s drawing national attention because control of the Senate is at stake and Hawaii’s contest is expected to be one of the most closely fought. Lingle, who won two governor’s elections, the first time beating Hirono, is a strong contender for the Republican Party. She has already shown her ability to out fundraise her potential Democratic opponents and she’s the only one in the field who’s won a statewide race at the top of a ticket. (Read Civil Beat’s story on the results of its poll on the possible general election match-ups.)

The Civil Beat Poll is the most recent public measure of the race. It’s a snapshot of voter opinion at the time the poll was taken, nearly seven months before the election. Much will happen during the campaign that could affect the outcome.

While each campaign has released a poll1 showing it with a strong lead, the only other independent poll of the race also showed a close contest. A poll by Public Policy Polling released on Oct. 19 showed Hirono leading with 45 percent to Case’s 40 percent, with Hirono’s lead built on support from the most liberal voters. It found Case leading with every other ideological group. The margin of error for the Democratic primary portion of the poll was +/- 5.1 percent.

There are a number of dynamics affecting the Democratic primary, but the biggest appears to be that Hirono is stronger among hard-core Democrats while Case is stronger among Republicans and independents. It would appear that the more politically diverse the turnout for the primary, the better it would be for Case.

Among voters who identify as Democrats, Hirono leads 51 percent to 34 percent. Case dominates among Republicans, 55 percent to 19 percent and is on top among independents, 47 percent to 36 percent. Bottom line: It would be best for Hirono to have as many Democrats as possible cast their ballots, and as few Republicans and independents decide to vote in the Democratic primary. It’s the opposite for Case. What would benefit him would be a strong pull to the polls and to vote in the Democratic primary for independents and even Republicans.

The need for a big turnout could be a challenge for Case, given the generally low voter turnout for primaries in Hawaii and the heavy labor union support for Hirono. The unions will be expected to turn out voters on her behalf.

But a hot, three-way mayoral race in Honolulu, where Case is stronger than Hirono, could boost voter participation. (The mayoral race is non-partisan.) And a five-person race in the Democratic primary for the 2nd Congressional District seat now held by Hirono could do the same. The GOP has not yet fielded a candidate, so it’s likely the primary winner will be the district’s next representative.

Here are some other key findings of the poll (Review the complete results at the bottom of this article):

The Obama Factor. President Barack Obama retains his strong approval ratings in Hawaii, especially among Democrats. And this is where Hirono’s strength is clearly visible. Of those who approve strongly of Obama, 54 percent support Hirono and 33 percent back Case. The two are very close when it comes to those who approve of the president somewhat, with Hirono’s edge dropping to 42 percent to 39 percent. But among those who disapprove of the president’s performance, Case dominates, with 50 percent versus 21 percent of those who disapprove somewhat and 72 percent to 6 percent of those who disapprove strongly supporting Case.

Who’s leading in the district both have represented? Hirono, the sitting congresswoman from the 2nd Congressional District, has a narrow edge there, 43 percent to 38 percent. But Case turns the table in the 1st Congressional District, where he has a bigger margin, 46 percent to 34 percent.

Man vs. woman. In this race, gender does seem to matter. Case, 59, fares much better with men, with 46 percent picking him and just 36 percent opting for Hirono. However, Hirono, who is 64, appears to have a slight edge among women, 41 percent to 38 percent.

The youth vote. Among older voters, the candidates are basically even. But younger voters, who are less likely to vote, favor Case. He leads among voters ages 35-49 with 42 percent compared with 35 percent for Hirono. Among voters ages 18-34, 54 percent back Case and just 26 percent support Hirono.

Ethnicity. While Case has a strong edge among Caucasians and Chinese, Hirono has the edge among Japanese, Filipino and Hawaiian voters.

Income. The more money voters have, the more likely they are to vote for Case. While voters with household incomes of $50,000 or less are more likely to support Hirono, 42 percent to 36 percent, the figures are reversed when it comes to households earning between $50,000 and $100,000, and the gap widens even more for households earning more than $100,000.

County. Case has the edge on Oahu, 46 percent to 35 percent, but Hirono leads in Maui, Kauai and Hawaii counties.

Many factors will affect the coming months. Hirono has more money than Case, and she has the backing of the Democratic political establishment, including unions. She is in office and hasn’t yet shifted to full campaign mode.

A comparison of the candidates’ websites shows a difference between their campaigns so far. Hirono’s website has almost no information about the candidate and nothing about her daily activities. Case, on the other hand, has a much richer and more active website.

Case has been more active as a candidate. He began airing TV ads after the poll was completed. When Honolulu held its Chinese New Year’s parade, Case walked the route shaking hands with onlookers. Other federal candidates were present, including 1st Congressional District Rep. Colleen Hanabusa and 2nd Congressional District hopeful Tulsi Gabbard. But Hirono was absent.